Improvement in lathes



J. F. CRAWFORD. i

LATHE Patented May 1,6, 18.76.

lUNITED STATES PATENT EEIOE.

JOSEPH F. CRAWFORD,`OF OAZENOVIA, NEW YORK.

IMPRCVEMENTlN LATHES.

Specification forming part of Letters Patent No. 177,475, dated May 16, 1876; application filed April 10, 1876.

lbA all whom it may concern f Be it known that I, JOsEPH F. CRAWFORD, of Gazenovia, in the county of Madison and State of New York, have invented certain Improvements in Lathes, Flaming-Machines, &c., of which the following is a specification:

The object of my invention is to provide a cheap method of constructing the Ways or guides of lathes, planing and milling machines, and other similar machines in which sliding heads or carriages are used; and to4 i thls end it consists in the combination of a main frame or support, and round or Oval rods secured thereon to form the yvays or guides, and in providing the frame with ribs or pillow-blocks to sustain and hold the rods, as hereinafter explained.

Hitherto the almost universal plan lhas been to cast the frames of metal-working lathes, planers, and similar machines, with the ways or guides thereon, the ways heilig linished and trued up for use by means of a planing-machine. The construction of the machines inI this manner is attended with great expense and difficulty, Owing to the time and expense required in planing' up the ways, and the difficulty of handling the frame in so doing when it is of large size. It is to overcome these difficulties, cheapen the cost of the machines, and produce guides superior to those of cast-iron, that my construction is designed. 4 v

In constructing a machine on my plan, whether it be a lathe, planer, or milling-ma` chine, I make the frame as usual, except that I omit the customary wayor guide, and either make the top face plain and iiat, or provide it at regular intervals with small transverse ribs or pillowb1ocks. Lengthwise on-the top face of the frame 1 place, as a substitute for each of the usual waysor guides, a drawn, rolled, or otherwise finished rod of metal, of a round or elliptical form in cross-section, and secure it rigidly in place by screws, bolts, or rivets, takin care to keep it perfectly true and straig t.

In practice, I rind I can produce round or elliptical rods by drawing or cold-rolling of almost absolute accuracy and straightness, and of a smoothness and hardness excelling vthat of the ordinary ways, and that, by applying these rods without further nishing or preparation carefully, in the manner described, I can produce ways which are both better and cheaper than those made as usual.

The rods may be applied to the plain flat face of the frame; but it is preferred to employ the ribs or pillow blocks having their upper faces made concave to receive and hold the rods. These ribs give a rm support to the rods, and, presenting but little surface, they can be cheaply trued up so as to give a firm bearing to the rods.

When the ribs are not used the frame is made as straight as possible, and the rods supported over low points therein by thin metal strips placed under them.

Figure l represents a side view of a frame of my improved construction; and Fig. 2 an end view of the same, A representing the frame, B the guide rod or way, and C the ribs.

This constructionA -avoids the heavy labor and expense of planing the ways, and thereby greatly reduces the cost of building the machine, while at the same time I produce better and smoother Ways, admit of the ways being readily `and cheaply renewed when Worn or injured, and also admit of the use of wrought-iron, steel, or composition ways on a cast frame.

I do not claim, broadly, a removable way or guide, as I am aware that they have been used in many places; but, having discovered that I can produce the round or loval rods, and apply them cheaply and practically to form the ways of lathes, dto.,

1. As an improvement in turning-lathes and similar machines, a cast-metal frame, A, having a round or elliptical rod, B, of rolled, drawn, Or finished metal applied thereto, as shown and described, to form a way or guide.

2. The combinationof a main frame, A, provided withthe ribs O and the round or oval rod B secured thereon, as described and shown.

3. The combination of a main way or frame, A, and a round or oval guide-rod, B, as shown, and for the purpose described.

JOSEPH F. CRAWFORD.

VWitnesses:

S. E. BROWN, M. O. BRIEN. 

